The field of antenna design is continuously adapting to the needs of the telecommunications industry. For some applications, multiple port antenna systems are desirable. Similarly, other applications may require not just multiple port antennas but also antennas which can be used for both high and low band frequencies. Finally, in other applications, antennas which can achieve specific beamwidths are required.
There are currently narrow band applications for antennas with four ports that can achieve 90 degree azimuth beamwidth. It has been suggested that increasing the height of a dipole antenna will increase azimuth beamwidth. Unfortunately, this technique cannot be applied to hex-port antennas. Firstly, increasing the height of the high band dipole to achieve 85 to 90 degree beamwidth generates a strong resonance in the low band spectrum. This resonance severely degrades the low band antenna pattern. Secondly, increasing the height of the low band dipole antenna increases the depth of the antenna. Finally, increasing the height of the high band and low band dipoles increases the cost of the antenna.
In another approach, it has been suggested that an 85 to 90 degree beamwidth can be achieved by using a small reflector, proper fencing, and by stacking the antenna columns. However, this method results in multi-column antennas that are impractically tall.
There is therefore a need for systems and devices which mitigate if not overcome the shortcomings noted above.